Python datetime.astimezone方法代码示例

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def convert_date(self, date_string):
        """Converts date from string format to date object, for use by DateField."""
        if date_string:
            try:
                # TODO: for now, return as a string.
                # When actually supporting DateField, then switch back to date.
                # ciso8601.parse_datetime(ts).astimezone(pytz.utc).date().isoformat()
                return self.date_field_for_converting.deserialize_from_string(date_string).isoformat()
            except ValueError:
                self.incr_counter(self.counter_category_name, 'Cannot convert to date', 1)
                # Don't bother to make sure we return a good value
                # within the interval, so we can find the output for
                # debugging.  Should not be necessary, as this is only
                # used for the column value, not the partitioning.
                return u"BAD: {}".format(date_string)
                # return self.lower_bound_date_string
        else:
            self.incr_counter(self.counter_category_name, 'Missing date', 1)
            return date_string 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def datetime_exists(dt, tz=None):
    """
    Given a datetime and a time zone, determine whether or not a given datetime
    would fall in a gap.

    :param dt:
        A :class:`datetime.datetime` (whose time zone will be ignored if ``tz``
        is provided.)

    :param tz:
        A :class:`datetime.tzinfo` with support for the ``fold`` attribute. If
        ``None`` or not provided, the datetime's own time zone will be used.

    :return:
        Returns a boolean value whether or not the "wall time" exists in
        ``tz``.

    .. versionadded:: 2.7.0
    """
    if tz is None:
        if dt.tzinfo is None:
            raise ValueError('Datetime is naive and no time zone provided.')
        tz = dt.tzinfo

    dt = dt.replace(tzinfo=None)

    # This is essentially a test of whether or not the datetime can survive
    # a round trip to UTC.
    dt_rt = dt.replace(tzinfo=tz).astimezone(tzutc()).astimezone(tz)
    dt_rt = dt_rt.replace(tzinfo=None)

    return dt == dt_rt 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def datetime_exists(dt, tz=None):
    """
    Given a datetime and a time zone, determine whether or not a given datetime
    would fall in a gap.

    :param dt:
        A :class:`datetime.datetime` (whose time zone will be ignored if ``tz``
        is provided.)

    :param tz:
        A :class:`datetime.tzinfo` with support for the ``fold`` attribute. If
        ``None`` or not provided, the datetime's own time zone will be used.

    :return:
        Returns a boolean value whether or not the "wall time" exists in
        ``tz``.

    .. versionadded:: 2.7.0
    """
    if tz is None:
        if dt.tzinfo is None:
            raise ValueError('Datetime is naive and no time zone provided.')
        tz = dt.tzinfo

    dt = dt.replace(tzinfo=None)

    # This is essentially a test of whether or not the datetime can survive
    # a round trip to UTC.
    dt_rt = dt.replace(tzinfo=tz).astimezone(UTC).astimezone(tz)
    dt_rt = dt_rt.replace(tzinfo=None)

    return dt == dt_rt 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def to_local_timezone(self, datetime):
        """Returns a datetime object converted to the local timezone.

        :param datetime:
            A ``datetime`` object.
        :returns:
            A ``datetime`` object normalized to a timezone.
        """
        if datetime.tzinfo is None:
            datetime = datetime.replace(tzinfo=pytz.UTC)

        return self.tzinfo.normalize(datetime.astimezone(self.tzinfo)) 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def to_utc(self, datetime):
        """Returns a datetime object converted to UTC and without tzinfo.

        :param datetime:
            A ``datetime`` object.
        :returns:
            A naive ``datetime`` object (no timezone), converted to UTC.
        """
        if datetime.tzinfo is None:
            datetime = self.tzinfo.localize(datetime)

        return datetime.astimezone(pytz.UTC).replace(tzinfo=None) 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def normalize_time(self, event_time):
        """
        Convert time string to ISO-8601 format in UTC timezone.

        Returns None if string representation cannot be parsed.
        """
        datetime = ciso8601.parse_datetime(event_time)
        if datetime:
            return datetime.astimezone(pytz.utc).isoformat()
        else:
            return None 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def extended_normalize_time(self, event_time):
        """
        Convert time string to ISO-8601 format in UTC timezone.

        Returns None if string representation cannot be parsed.
        """
        datetime = dateutil.parser.parse(event_time)
        if datetime:
            return datetime.astimezone(pytz.utc).isoformat()
        else:
            return None 

# 需要导入模块: import datetime [as 别名]
# 或者: from datetime import astimezone [as 别名]
def resolve_imaginary(dt):
    """
    Given a datetime that may be imaginary, return an existing datetime.

    This function assumes that an imaginary datetime represents what the
    wall time would be in a zone had the offset transition not occurred, so
    it will always fall forward by the transition's change in offset.

    .. doctest::

        >>> from dateutil import tz
        >>> from datetime import datetime
        >>> NYC = tz.gettz('America/New_York')
        >>> print(tz.resolve_imaginary(datetime(2017, 3, 12, 2, 30, tzinfo=NYC)))
        2017-03-12 03:30:00-04:00

        >>> KIR = tz.gettz('Pacific/Kiritimati')
        >>> print(tz.resolve_imaginary(datetime(1995, 1, 1, 12, 30, tzinfo=KIR)))
        1995-01-02 12:30:00+14:00

    As a note, :func:`datetime.astimezone` is guaranteed to produce a valid,
    existing datetime, so a round-trip to and from UTC is sufficient to get
    an extant datetime, however, this generally "falls back" to an earlier time
    rather than falling forward to the STD side (though no guarantees are made
    about this behavior).

    :param dt:
        A :class:`datetime.datetime` which may or may not exist.

    :return:
        Returns an existing :class:`datetime.datetime`. If ``dt`` was not
        imaginary, the datetime returned is guaranteed to be the same object
        passed to the function.

    .. versionadded:: 2.7.0
    """
    if dt.tzinfo is not None and not datetime_exists(dt):

        curr_offset = (dt + datetime.timedelta(hours=24)).utcoffset()
        old_offset = (dt - datetime.timedelta(hours=24)).utcoffset()

        dt += curr_offset - old_offset

    return dt